Alcohol consumption, tobacco smoking, betel quid chewing and oral health associations with hypopharyngeal cancer among men in Central South China: a case–control study

Figures & data

Table 1 Distributions of selected characteristics among cases and controls

Characteristics	Case(n=278)n%	Control(n=693) n%	p-value
Age (year)			p=0.110 ^a
≤50	46(16.5)	139(20.1)
51–60	106(38.1)	284(41.0)
61–70	103(37.1)	236(34.0)
>70	23(8.3)	34(4.9)
BMI (kg/m2)			p<0.0001 ^a
<18.5	45 (16.2)	29 (4.2)
18.5–24.0	164 (59.0)	409 (59.0)
>24.0	69 (24.8)	255 (36.8)
Income			p<0.0001^a
<2000	130 (46.8)	198 (28.6)
2000–4000	106 (38.1)	(46.6)
>4000	42 (15.1)	172 (24.8)
Education level			p<0.0001^a
Less and primary school	89 (32.0)	137 (19.8)
Junior and senior high school	150 (54.0)	459 (66.2)
More and junior college	39 (14.0)	97 (14.0)
Residence			p=0.015^a
Rural area	148 (53.2)	309 (44.6)
Urban area	130 (46.8)	384 (55.4)
Alcohol drinking			p<0.0001^a
Never	20 (7.2)	317 (45.7)
Ever	258 (92.8)	376 (54.3)
Tobacco smoking			p<0.0001^a
Never	18 (6.5)	239 (34.5)
Ever	260 (93.5)	454 (65.5)
Areca chewing			p<0.0001^a
Never	197 (70.9)	577 (83.3)
Ever	81 (29.1)	116 (16.7)
Oral hygiene			p<0.0001^a
Normal oral hygiene	200 (71.9)	472 (68.1)
Poor oral hygiene	78 (28.1)	84 (12.1)

Note: ^aPearsonχ² test was used to compare the differences between the case and control.

Table 2 The risk of alcohol consumption in hypopharyngeal cancer

Variable	Case(n)	Control (n)	Adjust OR^a(95%CI)	p-value
Alcohol drinking				p<0.0001 ^b
Never	20	317	1 (reference)
Ever	258	376	7.37(4.44–12.24)
Age at starting drinking				ptrend<0.0001^c
Never drinking	20	317	1 (reference)
≤18	58	80	9.20(5.01–16.91)
>18	200	296	6.89(4.10–11.56)
Duration, year				ptrend<0.0001^c
Never drinking	20	317	1 (reference)
≤20	58	104	6.62 (3.66–11.99)
21~39	127	211	6.71 (3.92–11.47)
>39	73	61	10.44 (5.64–19.32)
Ethanol-grams, daily				ptrend<0.0001^c
Never drinking	20	317	1 (reference)
≤20	46	195	2.71 (1.50–4.89)
21–80	110	138	8.67 (5.00–15.04)
>80	102	43	27.31(14.62–51.02)
Cumulative, glass-year				ptrend<0.0001^c
Never drinking	20	317	1 (reference)
<25	19	169	1.37 (0.69–2.72)
25–124	110	133	9.34 (5.39–16.19)
>124	129	74	18.16 (10.25–32.15)
Quitting years				ptrend=0.0056^c
Continue drinking	207	273	1 (reference)
1–4	29	51	0.60 (0.35–1.02)
5–9	16	30	0.70 (0.36–1.36)
>9	6	22	0.30 (0.12–0.80)
Drinking cessation	51	103	0.72 (0.58–0.90)
Alcohol type
Never drinking	20	317	1 (reference)
Traditional liquor(TL)^d	134	134	11.26 (6.53–19.41)	p<0.0001^b
Commercial liquor(CL)	77	126	6.63 (3.76–11.69)	p<0.0001^b
TL & CL	36	60	7.53 (3.84–14.79)	p<0.0001^b
Beer and wine	11	56	2.42 (1.06–5.56)	p=0.0368^b

Notes: ^aAdjusted for BMI, income, chewing andsmoking habits, and oral hygiene. ^bEstimates from multivariate unconditional logistic regression equations. ^cp_trend was calculated by unconditioned logistic regression after converting the variable into ranked data. ^dTraditional Liquoris defined as made in small workshops with crude manufacturing process, commercial Liquor is defined as made in distilleries with standard manufacturing process.

Abbreviations: TL, traditional liquor; CL, commercial liquor.

Figure 1 Comparison of formaldehyde concentration in traditional liquor and commercial liquor samples. Formaldehyde concentration in traditional liquor samples (n=38) was higher than that in commercial liquor samples (n=33, p=0.045). p-value was tested by Wilcoxon rank sum test. Circles represent outlier value, asterisks represent extreme value.

Table 3 The risk of tobacco consumption in hypopharyngeal cancer

Variable	Case (n)	Control (n)	Adjust OR(95% CI)^a	p-value
Tobacco smoking				p<0.0001 ^b
Never	18	239	1 (reference)
Ever	260	454	4.35 (2.51–7.53)
Age at starting smoking				ptrend=0.0004^c
Never smoking	18	239	1 (reference)
≤18	87	114	5.67 (3.07–10.46)
>18	173	340	3.89 (2.22–6.82)
Duration, year				ptrend<0.0001^c
Never smoking	18	239	1 (reference)
≤20	36	104	3.11(1.58–6.11)
21~39	121	224	4.28 (2.40–7.64)
>39	103	126	5.25 (2.87–9.60)
Cigarette, daily				ptrend<0.0001^c
Never smoking	18	239	1 (reference)
<20	44	92	3.09 (1.60–5.96)
20–39	150	286	4.25 (2.41–7.50)
>39	66	76	6.40 (3.35–12.21)
Cumulative, pack-year^d				ptrend<0.0001^c
Never smoking	18	239	1 (reference)
≤20	43	91	3.56 (1.83–6.93)
20–39	97	189	4.22 (2.33–7.62)
>39	120	174	4.87 (2.71–8.74)
Quitting years				ptrend=0.0097^c
Continue smoking	225	328	1 (reference)
1–4	12	56	0.35 (0.17–0.73)
5–9	13	33	0.60 (0.28–1.26)
>9	10	37	0.51 (0.23–1.15)
Smoking cessation	35	126	0.74 (0.59–0.93)

Notes: ^aAdjusted for BMI, income, chewing and smoking habits, and oral hygiene. ^bEstimates from multivariate unconditional logistic regression equations. ^cp_trend was calculated by unconditioned logistic regression after converting the variable into ranked data. ^d20 cigarettes in a pack.

Table 4 Alcohol consumption and tobacco smoking interaction parameters and attributable risks for hypopharyngeal cancer by age

Variable	Case (n)	Control (n)	Adjust OR(95%CI)^a	p-value ^b	PAR^c
A. Never alcohol and tobacoo	6	156	1 (reference)
Alcohol alone	12	83	3.41 (1.13–10.27)	0.0295	25.5%
Tobacco alone	14	161	2.21 (0.76–6.44)	0.1472	17.5%
Tobacco and alcohol combined	246	293	9.84 (6.49–14.92)	<0.0001	54.5%
Total	278	693
B. Less than 60
Never alcohol and tobacoo	5	91	1 (reference)
Alcohol alone	9	61	3.56(0.91–13.89)	0.0676	26.5%
Tobacco alone	10	100	2.11(0.61–7.33)	0.2421	18.5%
Tobacco and alcohol combined	128	171	7.51(4.56–12.36)	<0.0001	51.4%
Total	152	423
Older than 60
Never alcohol and tobacoo	1	65	1 (reference)
Alcohol alone	3	22	9.50(0.86–105.36)	0.0668	20.9%
Tobacco alone	4	61	5.02(0.44–57.48)	0.1945	12.5%
Tobacco and alcohol combined	118	122	17.06(7.71–37.74)	<0.0001	62.1%
Total	126	270

Notes: ^aAdjusted for BMI, income, chewing and smoking habits, and oral hygiene. ^bEstimates from multivariate unconditional logistic regression equations. ^cPAR, population attributable risk.

Table 5 Betel quid consumption and oral health with the risk of hypopharyngeal cancer

Variable	Case (n)	Control (n)	Adjust OR(95%CI)^a	p-value
A. Betel quid chewing
Areca chewing				p^b=0.0019
Never	197	577	1 (reference)
Ever	81	116	1.86 (1.26–2.75)
Duration, year				ptrend=0.0008 ^c
Never chewing	197	577	1 (reference)
≤10	8	29	0.96 (0.38–2.45)
11~20	51	87	2.09 (1.38–3.17)
Betel-grams,frequency				ptrend=0.0011 ^c
Never chewing	197	577	1 (reference)
<20	20	36	1.41(0.70–2.80)
20–39	43	80	2.06 (1.32–3.21)
Cumulative, pack-year				ptrend=0.0011 ^c
Never chewing	197	577	1 (reference)
≤10	20	39	1.39 (0.70–2.74)
11–20	31	77	2.08 (1.33–3.24)
Quitting years				ptrend=0.0068 ^c
Continue chewing	63	73	1 (reference)
1–4	12	27	0.43 (0.18–1.08)
>5	3	16	0.21 (0.06–0.74)
Chewing cessation	18	43	0.45 (0.26–0.79)
B. Oral health
Oral hygiene^c				p^b=0.0006
Normal oral hygiene	200	472	1 (reference)
Poor oral hygiene	78	84	2.07 (1.37–3.14)
Tooth loss				ptrend=0.0453 ^c
No	94	265	1 (reference)
1–5	121	220	1.04 (0.72–1.51)
>5	63	71	1.75 (1.08–2.83)
Dental visits				p=0.1634 ^d
No	216	374	1 (reference)
Yes	62	182	0.79(0.54–1.15)
Tooth Brushing				p=0.8612 ^d
No	38	70	1 (reference)
Yes	240	486	1.15 (0.72–1.85)

Notes: ^aAdjusted for BMI, income, chewing and smoking habits, and oral hygiene. ^bEstimates from multivariate unconditional logistic regression equations. ^cp_trend was calculated by unconditioned logistic regression after converting the variable into ranked data. ^dp-values were estimated by Pearsonχ² test.

Table S1 Comparison of traditional and commercial liquor consumptive volume

Variable	Case (n)	Control (n)	p^a value
Alcohol volume (TL, L/week)
<0.1	0	23
0.1-1	23	35	<0.0001
1-2	56	33
>2	55	13
Alcohol volume (CL, L/week)
<0.1	1	30
0.1-1	34	47	<0.0001
1-2	27	21
>2	15	2

Note: ^aP-values were estimated by Pearsonχ² test to compare the difference between case and control TL, traditional liquor; CL, commercial liquor